Pre-operative high sensitive C-reactive protein predicts cardiovascular events after coronary artery bypass grafting surgery: A prospective observational study

Abstract

C-reactive protein is a powerful independent predictor of cardiovascular events in patients with coronary artery disease. The relation between C-reactive protein (CRP) concentration and in-hospital outcome, after coronary artery bypass grafting (CABG), has not yet been established. The study aims to evaluate the predictive value of pre-operative CRP for in-hospital cardiovascular events after CABG surgery. High-sensitivity CRP (hs-CRP) levels were measured pre-operatively on the day of surgery in 66 patients scheduled for elective on pump CABG surgery. Post-operative cardiovascular events such as death from cardiovascular causes, ischemic stroke, myocardial damage, myocardial infarction and low output heart failure were recorded. During the first 30 days after surgery, 54 patients were free from observed events and 14 developed the following cardiovascular events: 10 (15%) had myocardial damage, four (6%) had low output heart failure and two (3%) suffered stroke. No patients died during the follow-up period. Serum concentration of hs-CRP > or = 3.3 mg/l (cut-off point obtained by ROC analysis) was related to higher risk of post-operative cardiovascular events (36% vs 6%, P = 0.01), myocardial damage (24% vs 6%, P = 0.04) and low output heart failure (12% vs 0%, P = 0.04). Multivariate logistic regression analysis showed that hs-CRP > or = 3.3 mg/l ( P = 0.002, O.R.: 19.3 (95% confidence interval (CI) 2.9-128.0)), intra-operative transfusion of red blood cells ( P = 0.04, O.R.: 9.9 (95% C.I. 1.1-85.5)) and absence of diuretics in daily antihypertensive treatment ( P = 0.02, O.R.: 15.1 (95% C.I. 1.4-160.6) were independent predictors of combined cardiovascular event. Patients having hs-CRP value greater or equal to 3.3 mg/l pre-operatively have an increased risk of post-operative cardiovascular events after on pump coronary artery bypass grafting surgery.